The Mass Spectrometry Center for the Research Triangle Region provides centralized high and low resolution mass spectrometric services for over fifty researchers in the Middle Atlantic Region, who are engaged in biomedical studies. These services involve the identification and structure elucidation of natural products, drug metabolites, and other substances of biological interest. The service also provides quantitative information in various types of mechanistic studies involving stable isotopes, such as D2, C13, O18 and N15. The results are made available by the use of sophisticated, computer controlled data processing techniques.